Giant crown-shaped polytungstate formed by self-assembly of CeIIIstabilized dilacunary Keggin fragments
S. Reinoso, M. Giménez-Marqués, J. R. Galán-Mascarós, P. Vitoria, J. M. Gutiérrez-Zorrilla
Angew. Chem. Int. Ed. 2010, 49, 8384-8388
Abstract: The largest tungstogermanate and third-largest polytungstate (see picture) was obtained by K+-directed self-assembly of three unprecedented types of [GeW10O38]12− fragments stabilized by coordination of Ce ions on the vacancies. In its Ce6O42 central ring, which displays antiferromagnetic interactions, a K+ cation is captured by internal water molecules. Gray octahedra WO6, green tetrahedra GeO4; Ce orange, K purple, O red.